After build QTcreator with mingw32, what more must I do ?

[Timoteo]

Okay, gotcha. I've never built Creator itself so I always suspected that the local lib might differ in some other way. There's no reason why you couldn't update the libs without messing with Creator, though, as long as you stay within the same major version.

Edit: Ahh. A 32bit Creator needs to be able to build a 64bit target.